Method of wiring contact pins



Feb. 12, 1929.

G. W. GOOD-RIDGE mac or WIRING conncr PINS Filed Oct. 6, 1925 anowtoz GILBERT IV. Goon/9106:

Patented Feb. 12, 1929- UNITED STATES PATENT OFFICE.

GILBERT W. GOODRIDGE, OI FAIRIIELD, CONNECTICUT, ASS IGNOB TO THE DEAD CHAIN MANUFACTURING COMPANY, 01 BRIDGEPOBT, CONNECTICUT, A CORPORA- TION OI CONNECTICUT.

METHOD or wmm'e oon'rac'r rma Application filed October 6, 1925. Serial No. 60,898.

My invention relates to method of wiring contact pins.

In electric fittings of various types, such as audions, lamps, etc., contact pins are se- 5 cured to the insulating base of the fit-' ting and lead wires are permanentl soldered to the pins. The common practice eretofore has been to employ pins formed from rod stock, out to length and bored to receive the lead wire.

The leadwirc Whichiscarrieddownthrough the central bore of the pin, is commonly secured at the contact end of the latter by extcrnally applied solder. Adherent solder, however, so enlarges the pin end that a further operation upon the contact is necessary to remove the excess solder and thus maintain the pins diameter with approximate exactitude. The necessity for approximate exactness of diameter will be appreciated when it is-considered that the pins of an audion bulb base, for instance, differ in diameter, and that the holes in a cooperating receptacle through which the pins pass to engage the receptacle terminals, are accurately calibrated to insure the proper polarity position'of the audion in the receptacle.

My invention provides a method of wiring which obviates the ditficulties mentioned. I

In the accompanying drawin Figs. 1 to 5 inclusive illustrate my method of connecting lead wires to the contact pins. While my invention, in some aspects, is applicable to pins of other type than that illustrated in the accompanym drawings, desirable y the sheet metal pin shown is reason of its economy. Pins of this general type form the subject matter of the copending applications of William J. Gagnon, Ser. ,Nos.'56,291 and 56,292, filed September 14, 1925. x l s I have illustrated my invention in connection with anaudion base; but it will be realized thatits utilit is not confined to this particular type of tting.

As here s own, the audion comprises a glass base 15 carried by a surrounding metal shell 16, which supports the usual bulb 17. Lead wires 18.from the usual grid, filament and plate elements (not shown) pass through the lower end of the bulb and entercorresponding. contact pins 19, the heads 20 of which are embedded inthe glabasm At the .contact ends of the pins, the lead wires are secured by solder 21.

As pointed out in the Gagnon applications above referred to, the pins are shaped from sheet metal stock and are longitudinally split from end to end. The embedded head 20' exceeds the pin shank in diameter, and is also preferably non-circular, at least in part, as at 22, in order to hold the pin agaihst rotation in the base.

The base, with the pins thus embedded therein, is now ready for the reception of the lead wires from the bulb. Instead of follow ing the usual practice, however, of passing the lead wires through the pins and connecting by externally applied solder,-I effect the soldered connection within the pin. A bath of flux 32, which is pasty at normal tempera.- ture, is heated to fluid condition. The ends of the wire leads 18 of the bulb are momentarily dipped, sa to the depth of 1/ into the flux bath. Xfter the adherent flux has congealed upon the lead wires, the latter are passed into the several pins 19 on the base. As the fluxed ends of the wires pass through the'exit holes 33 at the rounded contact ends of the pins, more or less of the flux is scraped off at the holes 33 and gathered against the inner surfaces of the plus. The projecting ends of the wires may then be sni ped off.-

Thus assembled and prepared, t he'contact ends of the pins are dipped for a moment in a bath of hot solder 34. The aflinity of the latter for the flux causes it to enter the hollow pins through the end a ertures'33 thereof. The heat fromtheso der spatters the flux against the surroundin inner surfaces of the pin wall and a soli connection between t e solder, lead wire and pinis thus established within the contact end of the in. The absenceof flux fromv the outer-sur ace of the pin, coupled with the high temperature of the solder bath, prevents adhesion of the solder to the exterior of the pm in any substantial quantity. The pin may be sllghtl silvered by the solder, but no quantity suftibient to necessitate removal is depos ted thereon.

. While my improved method of the lead wires is preferably employed with his of the sheet metal type disclosed in the pins of other constructions. My method of attaching the lead wires to the pin can be employed withpins of various constructions.

It will also be understood that while I have 5 described my invention with'particular ref- 10 foregoing description is merely illustrative of the thoughts which underlie my invention, I claim 1. The method of connecting a lead wire mg an end of the lead wire with flux, passing said end through the pin untilits fluxed en is extended through said end opening and portion of the. flux is scraped off within the pin, and dipping said end of the pin in hot solder.

2, An electric fitting having a hollow contact pin with an end opening of less diameter than the interior diameter of the contact pin,

a lead Wire positioned within the contact pin and solder sealing said end opening and uniting the Wire and in Within the shank of the pm.

to a hollow in having at its contact end an 15 opening of ess diameter than the internal diameter of the pin, which comprises coat- In testimony whereof I have signed my :0 name to this s ecification.

GIL ERT W. GOODRIDGE. 

